Woody and Wallace attend a lecture on rocksalt, MacAllister and Riordan are on the graveyard shift while Henderson finds out there's more then one Argos in the city.

McAllister accidentally reveals his secret relationship with Michelle and must find a way of making it up to her. Meanwhile, Henderson suffers an allergic reaction.

Woody and Wallace are set to fail a mandatory drugs test until Wallace's granny provides the solution. McAllister invents a bogus girlfriend to make Michelle jealous.

Henderson and Toner are on the trail of a swan murderer. Riordan queues against his will for concert tickets.

Riordan and Michelle find some Air Raid shelters in the park while Woody and Wallace are on Night shift at the museum.