Marvel's Agents of S.H.I.E.L.D. Spoilers: War between S.H.I.E.L.D., Centipede heats up in midseason finale

The midseason finale of Marvel's Agents of S.H.I.E.L.D. airs on Tuesday and will show how the war between S.H.I.E.L.D. and the nefarious organization called Centipede will heat up in more ways than one.

The episode will feature some returning characters, including Mike Peterson (J. August Richards), who was the subject of the first case the team investigated in the pilot episode. Raina, the Girl in the Flower Dress, will also appear in the episode. We last saw her at the end of Episode 5 when she visited Edison Po (Cullen Douglas) in prison.

EW.com posted an exclusive clip from the episode in which Edison returns and Centipede decides to bust him out of jail. In the clip, an inmate tries to sit down to eat but Edison shoos him away. A group of seemingly powered-up Centipede agents bust in through the ceiling and fight the guards as Edison calmly eats his meal. One f them says "time to go" and Edison insists that he call him "sir." The agent does and they pull him up through the hole in the ceiling.

Check out the clip here.

Executive producer Jed Whedon recently told the "Mega Buzz" column at TV Guide that Centipede would be "making another appearance soon. We're going to see some old faces and get some more Centipede action going."

Agents of S.H.I.E.L.D. could use a season-long plot thread to tie everything together. Many of the episodes thus far have focused on individual cases and the mysteries of the main characters, but an overall plot would serve the show well.