She begged DSU Marianne Hamilton (Nadine Marshall) to let her return to work. Her boss caved unrealistically fast (hey, this is TV drama) on condition she had compulsory therapy sessions with Dr MacAndrew (Pippa Haywood of Brittas Empire and Bodyguard baddie fame).

More importantly, Lana’s top-knot and Ray-Ban Wayfarers were soon back on. She briefed her expo team on bomber Welsh and the tricksy techniques he uses, vowing: “I’m not losing anyone else.” With an episode-and-a-half still to go, we’ll see.

Bomber got political by targeting by-election

There was no time to ease herself back in. Lana and co were called to a security alert at South London University – the setting for a special by-election edition of an Any Questions-alike radio debate show, hosted by Simon Henley (comedian Miles Jupp in serious acting mode). In a marginal seat, left-leaning parties had formed a Progressive Alliance against English Flag, and tensions were running high due to the increased threat level.

A suspect package was hidden among the broadcast equipment – planted by Welsh, posing as a sound engineer. The location, with its multi-storey buildings and copious windows, recalled Westhaven Estate from episode one. Lana did her lucky handshake with sidekick Danny (Eric Shango) before venturing into the lecture theatre. She deliberately paired herself with her nemesis, suspected traitor John Hudson (Kris Hitchen). Things were about to get interesting.

“Me against the bomber. Me vs him”

We cut between Lana describing her methodology to Dr MacAndrew and her prickly banter with Walsh as they tackled the bomb. Like the Westhaven suicide vest, it had a decoy timer and used two phones for remote detonation – one to prime, one to trigger. While police searched for a suspect carrying two mobiles, Lana set up the pigstick (good to see her trusty disruptor back after a week off). Yet again, no were helmets worn.

Suddenly one of the phones rang. The device was armed. In a tense sequence, a police sniper spotted Welsh (a sinister silent role for actor Russ Bain) on a balcony overlooking the building, a phone in each hand. The marksman took him down. It took 18 minutes between the manhunt being launched and the kill shot. Sighs of relief all round but not for long. John walked away from the device and surreptitiously called it. As Lana sprinted clear, shouting “Hard cover!”, the bomb detonated. John was seen fleeing the scene. Why I oughta…

Bent copper™ had been hiding in plain sight

Mobile data showed Welsh had primed the device. When he was killed, Hudson took over and triggered it. The inside man had been Lana’s embittered, snaggle-toothed colleague all along. He’d first emerged as a suspect in episode two and now it was proven.